Toolholder

Abstract

The present invention provides a toolholder mountable on a lathe or other machine tool for supporting a cutting plate relative to a workpiece for cutting or shaping the workpiece. The toolholder including a body having a tapered tool base at one end thereof, the tool base defining a tool seat for supporting a cutting plate. A plug screw having a head defining threads on an outer surface thereof for engaging a threaded hole in the tool base is also provided. The plug screw further defining a shank extending eccentrically from the head, the shank being receivable through a mounting hole defined by the cutting plate for locating the cutting plate relative to the tool seat upon rotation of the plug screw relative to the tool base. A lock nut is provided for receiving a threaded end of the shank for securing the cutting plate to the tool base and toolholder.

What is claimed is: 
     
       1. A toolholder comprising:
 a body having a tapered tool base at one end thereof, said tool base defining a tool seat for supporting a cutting plate and a rear wall extending substantially perpendicular to said tool seat, wherein said tool seat leads to an undercut along a juncture of said tool seat and said rear wall for ensuring a cutting plate lies flat on said tool seat; 
 said tool base defining a threaded hole extending through said tool base and tool seat, said threaded hole being oriented substantially perpendicular to said tool seat; 
 a plug screw having a head at one end defining threads on an outer surface thereof for engaging said threaded hole, said plug screw including a shank extending eccentrically from said head along an axis parallel to the axis of said head, said shank defining a smooth middle portion and a threaded portion at an end opposite the head, whereby the plug screw has threads on the head at one end, threads on the eccentric shank at the end opposite the head, and the smooth middle portion therebetween; 
 said threaded head of the plug screw being receivable in said threaded hole defined by said tool base, wherein said shank extends outwardly from said tool seat when said head of the plug screw is received in said threaded hole, said smooth middle portion of said eccentrically extending shank being receivable in a mounting hole defined in a cutting plate for locating the cutting plate firmly against the rear wall upon rotation of said plug screw relative to said tool base; and 
 a lock nut for receiving said threaded portion of said shank, said lock nut for securing a cutting plate against the tool seat of said tool base. 
 
     
     
       2. The toolholder according to  claim 1  wherein said tool base is generally triangular-shaped forming one of a right-angled, a left-angled, and a straight toolholder. 
     
     
       3. The toolholder according to  claim 1  wherein said body further defines a tool recess for receiving the cutting plate, the tool recess defined in part by the tool seat. 
     
     
       4. The toolholder according to  claim 1  wherein said tool seat defines an angular surface for supporting a cutting plate and establishing a rake angle between the cutting plate and a workpiece. 
     
     
       5. The toolholder according to  claim 1  wherein one side of an outer diameter of the shank of the plug screw is generally aligned with the outer surface of the head thereof. 
     
     
       6. The toolholder according to  claim 1  wherein said plug screw further defines a slot or socket for turning the plug screw. 
     
     
       7. A toolholder comprising:
 a body defining a tapered tool base at one end thereof, said tool base partially defining a tool recess for receiving a cutting plate therein; 
 said tool base defining a tool seat for supporting a cutting plate; 
 a rear wall defined by said body extending substantially perpendicular to said tool seat, said rear wall further defining said tool recess; 
 said tool base defining a threaded hole therethrough, said threaded hole extending through said tool seat and oriented substantially perpendicular thereto; 
 a plug screw having a head defining threads on an outer surface thereof for engaging said threaded hole defined by said tool seat, said plug screw further defining a shank extending eccentrically from said head along an axis parallel to the axis of said head, said shank defining a smooth middle portion and a threaded end portion disposed at the end of the plug screw opposite from the threaded head; 
 said threaded head of the plug screw being receivable in said threaded hole defined by said tool base, wherein said shank extends outwardly from said tool seat and into said tool recess when said plug screw is received in said threaded hole, said smooth middle portion of said shank being receivable in a mounting hole defined in a cutting plate for locating the cutting plate firmly against said rear wall of said tool recess via eccentric rotation of said smooth middle portion of said plug screw relative to said tool base; and 
 a lock nut for receiving said threaded end portion of said shank, said lock nut for securing a cutting plate firmly against the tool seat of said tool base and tool holder after the cutting plate is located firmly against the rear wall of the tool recess. 
 
     
     
       8. The toolholder according to  claim 7  wherein said tool base is tapered to form one of a right angled, left angled or straight toolholder. 
     
     
       9. The toolholder according to  claim 7  wherein said tool seat defines an angle of inclination for providing a rake angle between the cutting plate and a workpiece. 
     
     
       10. The toolholder according to  claim 9  wherein said angle of inclination is about five degrees below a horizontal axis extending outwardly from said tool body at a juncture of said tool seat and said rear wall. 
     
     
       11. The toolholder according to  claim 7  wherein said tool seat defines an undercut disposed along a juncture of said tool seat and said rear wall of said tool recess for ensuring that the cutting plate lies flat on said tool seat, and wherein said rear wall extends substantially perpendicularly from said undercut. 
     
     
       12. A toolholder comprising:
 a body having a tapered tool base at one end thereof, said tool base defining a tool seat for supporting a cutting plate and a rear wall extending substantially perpendicular to said tool seat, wherein said tool seat defines an undercut along a juncture of said tool seat and said rear wall for ensuring the cutting plate lies flat on said tool seat, wherein said rear wall extends substantially perpendicularly from said undercut, and wherein said tool seat defines an angular surface for supporting the cutting plate and establishes a non-positive rake angle between the cutting plate and a workpiece; 
 said tool base defining a threaded hole extending through said tool base and tool seat, said threaded hole being oriented substantially perpendicular to said tool seat; 
 a plug screw having a head at one end defining threads on an outer surface thereof for engaging said threaded hole, said plug screw including a shank extending eccentrically from said head along an axis parallel to the axis of said head, said shank defining a smooth middle portion and a threaded portion at an end opposite the head; 
 said threaded head of the plug screw being receivable in said threaded hole defined by said tool base, wherein said shank extends outwardly from said tool seat when said head of the plug screw is received in said threaded hole, said smooth middle portion of said shank being receivable in a mounting hole defined in a cutting plate for locating the cutting plate firmly against the rear wall upon eccentric rotation of said plug screw relative to said tool base; and 
 a lock nut for receiving said threaded portion of said shank, said lock nut for securing a cutting plate against the tool seat of said tool base. 
 
     
     
       13. The toolholder according to  claim 12  wherein said tool base is generally triangular-shaped forming one of a right-angled, a left-angled, and a straight toolholder. 
     
     
       14. The toolholder according to  claim 12  wherein said body further defines a tool recess for receiving the cutting plate, the tool recess defined in part by the tool seat. 
     
     
       15. The toolholder according to  claim 12  wherein one side of an outer diameter of the shank of the plug screw is generally aligned with the outer surface of the head thereof. 
     
     
       16. The toolholder according to  claim 12  wherein said plug screw further defines a slot or socket for turning the plug screw.